Question

Before $3$ years, the average age of a five members family was $17$ years. A baby having been born and the average of family is now $17$ years. The present age of the baby is

• A. $3$ years
• B. $2$ years
• C. $1$ year
• D. None of these

Answer 1

Answer: (B)

$2$ years

Before $3$ years ago average age of $5$ members $=17$
Total age $=17\times 5=85$
Total present age of $5$ members $=85+15=100$
Present Average age of $6$ members $=17$
Age of child $=102-100=2years$.